Earlier this year Ayatollah Shahroudi ordered an end to public executions, unless they had his special approval.

He also banned publishing pictures and broadcasting video footage of executions.

The bans followed a spate of public executions last year which were widely covered by the international media and provoked global condemnation.

One of the two youths given a temporary reprieve on Wednesday said he had agreed to sign a confession without knowledge of its content after he had been tortured.

“I am a 21-year-old, a young man who was only 16 when he entered prison. Like any other teenager [I was] still living my children dreams,” Mohammad Feda’i wrote in a letter obtained by Amnesty International.

“I was beaten and flogged repeatedly… They hanged [suspended] me from the ceiling and left me with no hope of living.”

Feda’i was convicted of a murder committed in a snooker club in 2004. Amnesty says he acted in self-defence and that he was convicted after an unfair trial.

The two treaties are the International Covenant on Civil and Political Rights and the Convention on the Rights of the Child.